1. Field of the Invention
The present invention relates to a position control system in, for example, a numerical control device or an industrial robot system and a control method of the same. More specifically, this is a position control system which performs position control with high precision by correcting positional deviation caused by deformation, etc., due to the weight of the control part itself, and a method of the same.
2. Description of Related Art
For example, in the position control of a numerical control machine tool, usually the position control of the controlled object, such as a cutting tool, is carried out by detecting the rotational position of the servo motor for driving a movement mechanism which moves the cutting tool or other controlled part by a rotation detector, such as an encoder, attached to the servo motor and controlling the rotation of the servo motor based on this detected value.
In such a numerical control machine tool, there are cases where even if the control of the rotation of the servo motor is correctly carried out, correct position control of the cutting tool or other controlled object cannot be carried out due to positional deviation, distortion, etc., due to elastic deformation etc., caused in the mechanical elements forming the numerical control machine tool.
Currently, methods exist to solve this problem. However, they are imprecise, complicated, and involve other problems.